A number of families have been evacuated from their homes in Co Fermanagh while Army bomb disposal experts work to make the device safe.

The alert at Derrylin Road - the main arterial route between Enniskillen and Dublin - was raised early this morning but is expected to continue into tomorrow.

"Police in Fermanagh are continuing to deal with a suspicious vehicle on the Derrylin Road, Enniskillen. At this stage we believe we are dealing with a suspect device. The security operation is continuing," a spokeswoman for the Police Service of Northern Ireland (PSNI) said.

The finger of blame will be pointed at dissident republicans, who have murdered two soldiers, two policemen and a prison guard in their campaign of violence against the security forces.

A week ago the PSNI discovered a mortar type device aimed towards New Barnsley police station in north Belfast. Also last week three officers escaped injury when an explosive device detonated within metres of them as they patrolled a coastal path on the outskirts of Belfast.

Earlier this month two men were arrested after police intercepted a van carrying four mortar bombs which were primed and ready to fire at a station in Londonderry.

Ulster Unionist MLA in Fermanagh Tom Elliott condemned those responsible. He said: "Those who continue with their attempts to damage the community and cause as much difficulties for the people of Northern Ireland should catch themselves on and accept that the terrorist campaign failed in the past and will fail again."

Ulster Unionist Policing Board member Ross Hussey MLA added his disgust. He said: "On a day like today when half the country has ground to a virtual standstill due to the horrendous weather conditions, it is beneath contempt that some elements within our society should seek to cause further disruption."

Meanwhile, a separate security alert on the Belfast Road, Holywood in Co Down, caused major traffic disruption but was later declared a hoax.